1960～2007年福建省雷暴气候特征分析

Analysis on the Climate Characteristics of Thunderstorm in Fujian Province during 1960-2007

[目的]研究福建省雷暴活动特点和气候规律。[方法]利用1960～2007年福建省67个气象站的逐日雷暴资料,采用气候倾向率、趋势系数等方法,分析了福建省雷暴的时空分布特征。[结果]1960～2007年福建省的雷暴日数分布呈东北—西南走向,并从沿海向内陆逐渐递增。高值区在龙岩地区,沿海岛屿最少。48年福建省雷暴日数有明显减少的趋势,中部沿海地区减少速率为3.5d/10a,内陆山区大部分为4.5d/10a,宁德北部、三明东部及南平部分地区为5.5d/10a。雷暴日趋势系数变化有明显的区域特征,特别是内陆山区比沿海减少的趋势更加明显;减少最多的地方是南平地区的北部,趋势系数达-0.65;而中部沿海地区减少趋势不太明显,系数仅为-0.15。雷暴日有明显的季节变化,3～9月是雷暴的多发期,8月达最高值,9月开始迅速减少,从10月开始一直到次年2月都较少雷暴发生。平均初雷日西北部地区早于东南部地区,平均终雷日北部地区和南部地区差异不大。由于福建省北部和西部地区初雷日出现早,终雷日出现晚,造成全年雷暴活动时间比沿海长,两者相差近一个月。[结论]该研究为重大工程项目的气候可行性论证提供科学依据,为防雷减灾提供天气气候方面的理论依据,也对进一步研究福建雷暴的形成机理奠定基础。

[Objective]The research aimed to study the activity characteristics and climate rule of thunderstorm in Fujian Province.[Method] Based on the daily thunderstorm data in 67 meteorological stations of Fujian Province during 1960-2007,the spatial and temporal distribution characteristics of thunderstorm in Fujian Province were analyzed by using the climate tendency rate,the trend coefficient and so on.[Result]The distribution of thunderstorm days showed the northeast-southwest direction and gradually increased from the coast to the inland in Fujian Province during 1960-2007.The high value zone was in Longyan,and the thunderstorm days in the coastal islands were fewest.The thunderstorm days had the obvious decrease trend in Fujian Province in 48 years.The decrease speed in the central coast area was 3.5 d/10 a and was 4.5 d/10 a in most inland mountain areas.It was 5.5 d/10 a in the north of Ningde,the east of Sanming and some areas in Nanping.The variation of thunderstorm day trend coefficient had the obvious regional characteristic.Especially the decrease trend in the inland mountain area was more obvious than that in the coast.The decrease of thunderstorm day trend coefficient in the north of Nanping was the most,and the trend coefficient was-0.65.But the decrease trend in the central coast wasn’t obvious,and the coefficient was only-0.15.The thunderstorm day had the obvious seasonal variation.The multi-occurrence period of thunderstorm was during March-September,and it reached the maximum value in August.Started from September,the thunderstorm quickly decreased.From October to February in next year,there was less thunderstorms.The average first thunderstorm day in the northwest area was earlier than that in the southeast area.The difference of average final thunderstorm day in the north and south areas wasn’t big.For the first thunderstorm day in the north and west of Fujian was early,and the final thunderstorm day was later,the thunderstorm activity time in the whole year was longer than that in the coast,and they differed by nearly one month.[Conclusion]The research provided the scientific basis for the climate feasibility proof of major project items,and provided the theory basis about the weather climate aspect for the lightning prevention and disaster reduction,and also laid the foundation for further studying the formation mechanism of thunderstorm in Fujian.